(a) Graphical representation of 10 topics, combined to produce “documents” like those shown in b, where each image is the result of 100 samples from a unique mixture of these topics. (c) Performance of three algorithms on this dataset: variational Bayes (VB), expectation propagation (EP), and Gibbs sampling. Lower perplexity indicates better performance, with chance being a perplexity of 25. Estimates of the standard errors are smaller than the plot symbols, which mark 1, 5, 10, 20, 50, 100, 150, 200, 300, and 500 iterations.